[CO2 elimination via extracorporeal circulation in respiratory assistance: artificial lung or kidney? Experimental...

In the context of a respiratory assistance protocol dissociating oxygenation of the blood from elimination of carbon dioxide, it is possible to rest the lungs which are used for oxygen exchange by diffusion via functional zones. CO2 is eliminated via extracorporeal circulation. In order to simplify this method, the authors investigated the optimal conditions for this elimination at flow rates similar to those used for haemodialysis (0.33 l/min). This study was designed to evaluate the in vitro elimination of CO2 obtained by a membrane artificial lung with and without "doping" by acidification (10 ml/min of 0.01 N HCl) of the blood inlet compared with that obtained with a haemodialysis machine with and without alkalinisation (0.5 ml/min of 0.5 N NaOH) of the dialysate inlet. The results obtained showed that haemodialysis with an alkaline bath ensured CO2 elimination 36% superior to that of the artificial lung associated with acidification.